Well equity is easy, you take the number of cards that will complete your hand and divide it by the number of cards in the deck. With two cards to come you can generally double this number.

EV is much harder, when trying to calculate EV you have to factor in your opponents hand, the amount of their/your bet, the size of the pot, and your hand. Basically with EV you are trying to determine if the play you make (calling, folding, raising, etc...) shows a positive expectation when made. EV can mean many things, sometimes it means determining if a bluff will win you the pot enough times to be correct, or if your opponent will call a valuebet with worse hands enough to be for "value" or if you have a flush draw and your opponent bets a certain amount will calling be +EV.

I'll need some more concrete examples to show you how to calculate your EV in spots.